What a NAS Does
A NAS is a dedicated storage device — usually a small box with 2–8 drive bays — that connects to your router and presents shared storage over the network using SMB (Windows file shares), NFS (Linux/macOS), or both. Every device on your local network can read and write to the NAS. Speeds are limited only by your network (gigabit Ethernet = ~120 MB/s) and the drives.
Beyond file sharing, modern NAS devices run applications: Plex or Jellyfin for media streaming, a local backup target for Time Machine and Windows Backup, a surveillance station for security cameras, a personal cloud with web and mobile apps (similar to Dropbox), and Docker containers for any self-hosted software. Synology and QNAP are the dominant consumer NAS brands, with polished software interfaces that make setup approachable even without Linux experience.
What Cloud Storage Does
Cloud storage services (Google Drive, iCloud, Dropbox, OneDrive) store files on remote servers and sync them to your devices over the internet. Files are accessible from anywhere on any device without configuration. The provider handles hardware, redundancy, backups, and availability — you pay a monthly or annual subscription fee and use a client app.
The tradeoffs: your data lives on someone else's hardware (privacy concern), uploads/downloads are limited by your internet upload speed (often much slower than a NAS on a local network), and monthly costs compound over years. A 2TB iCloud plan at $10/month costs $120/year, or $600 over five years — enough to buy a capable NAS that stores far more data.
The 3-2-1 Rule: Why a NAS Still Needs Cloud
Even with a NAS, storing your only copy locally is insufficient for important data. The 3-2-1 rule: keep 3 copies of data, on 2 different media types, with 1 copy offsite. A NAS at home satisfies the local copy and the different media requirements, but not the offsite requirement. A fire, flood, or theft that destroys your home also destroys your NAS.
The practical combination for most users: a NAS as the primary local storage for capacity and speed, plus a selective cloud backup of critical data (documents, photos, irreplaceable files). Services like Backblaze B2 offer object storage at $6/TB/month — backing up 2TB of critical documents costs far less than replacing an entire cloud storage subscription for all files.
NAS vs Cloud Storage Comparison
| Factor | NAS (Home) | Cloud Storage |
|---|---|---|
| Upfront cost | $200–800 (NAS + drives) | $0 |
| Ongoing cost | ~$10–20/year (electricity) | $10–30/month for 2–6TB |
| Cost over 5 years (2TB) | ~$350–600 total | $600–1,800 total |
| Local access speed | 80–120 MB/s (gigabit LAN) | Limited by internet upload speed |
| Remote access | Via VPN or reverse proxy | Native; from any device |
| Storage capacity | Scalable (add drives); 4–40TB common | Limited by subscription tier |
| Privacy | Full — data stays on your hardware | Provider can access your files |
| Redundancy | RAID (protects vs drive failure only) | Provider manages; usually highly redundant |
| Offsite backup | Must set up separately | Inherent (files on remote servers) |
| Technical effort | Medium (initial setup) | Minimal |
| Best for | Large media collections, privacy focus | Easy access, non-technical users |
Frequently Asked Questions
How much does it cost to run a NAS at home?
A 2-bay NAS like a Synology DS224+ draws 15–25W idle. At average US electricity rates (~$0.16/kWh), that is $20–35/year to run 24/7. Add the initial purchase price of $200–350 for the NAS plus $80–160 per 4TB drive (two drives for RAID 1). Total first-year cost: $400–700, but subsequent years cost only electricity.
Can I access my NAS remotely like cloud storage?
Yes. Synology's QuickConnect and QNAP's myQNAPcloud provide easy remote access through the vendor's relay servers without opening firewall ports. Alternatively, set up a WireGuard VPN on your router to connect to your home network directly when away, giving full NAS access at LAN speeds (limited by your home internet upload speed). For maximum privacy, avoid vendor relay services and use a VPN.
What happens to my data if the NAS breaks?
If just the NAS unit fails (the box, not the drives), most NAS software (Synology, QNAP, TrueNAS) lets you move the drives to a replacement device and continue normally. If drives fail, RAID provides redundancy for single or dual drive failures (depending on RAID level). If you lose all drives simultaneously (unlikely but possible in a disaster), you need a backup. RAID is not a backup.
Is a NAS better than an external hard drive?
For home storage accessible by multiple devices, yes. An external drive connects to one computer at a time via USB. A NAS connects to your entire network over Ethernet, is accessible by all devices simultaneously, runs 24/7, and has drive redundancy. An external drive is fine for portable backups of a single computer; a NAS is better for shared household storage.